Conventionally, there has been used a thermal printer that has a thermal printer head including a row of heat-generating elements in a width direction. In such a thermal printer, paper, specifically thermal paper, passes between the thermal printer head and a platen roller. The platen roller rotates and is configured to be urged against the thermal printer head. In this configuration, the thermal printer head performs printing on the paper by applying a predetermined pressure to the paper.
Recently, a portable thermal printer has been developed. The portable thermal printer exhibits excellent mobility, since it can be carried anywhere by a user and be operated at a commercial place, especially where such mobility is required to input sales information such as a discounted price or a time-limited service for the sale of products.